T3 and T4 levels dont mean much either. They are a range compiled from average people. The only value the range has is if your not in it, then its a serious indication something is wrong.
T3/T4 value ranges is like driving a car without knowing how big the gas tank is.
A half a tank on the gauge of a 3 gallon gas tank is not the same as having a half a tank of a 25 gallon gas tank.
Most people who suffer hypo T symptoms are well within range. I know I was and always have been yet after being on Iodine for a year I have the metabolism I did when I was in my 20's.